In wellbore operations, cementing may be used to control migration of fluids outside a liner installed in the wellbore. For example, cement may be installed in the annulus between the liner and the formation wall to deter migration of the fluids axially along the annulus.
Often cement is introduced by flowing cement down through the wellbore liner to its distal end and forcing it around the bottom and up into the annulus where it is allowed to set. Occasionally it is desirable to introduce cement into the annulus without pumping it around the bottom end of the liner. A stage tool may be used for this purpose. A stage tool allows cement to be introduced to the annulus through the liner wall along the length of the liner.